1) Gluten protein structures can vary in wheat grain depending on cultivar, environmental conditions, and various applications. The amount and types of proteins, as well as their aggregation behavior, influence baking quality. 2) Polymeric protein formation in wheat is influenced by genotype, environment, and their interaction. Factors like time to anthesis, grain development period, temperature, and nitrogen availability can impact protein concentration and glutenin-gliadin relationships. 3) Additives can strengthen wheat gluten bioplastics by increasing tensile strength parameters like fracture stress and Young's modulus. Salicylic acid, sodium hydroxide, hemp fibre, and diamine additives showed various improvements.

1. Gluten protein structures;
Variation in wheat grain and at various applications
Eva Johansson
Agrosystems, SLU
Ali Malik
Abrar Hussain
Faisa Rasheed
Bill Newson
Tomas Plivelic
Mikael Hedenqvist
Mikael Gällstedt
Ramune Kuktaite

2. Reasons for proteins being
important
• Proteins
• Polymers
•Protein concentration
•Protein types • Largest in nature
•Amount of protein types
•Aggregation behaviour
Shewry et al. 2002

3. Baking quality – Protein structure
Protein composition - Genotype
1,2 140
1 120
LUPP
100
0,8 TUPP
80 Glugli
0,6
60 Prot
0,4 Glut
40
0,2 20
0 0
Triso
37346
37391
37342
37281
Dragon
Vinjett
Johansson et al. 1995
Johansson et al. 2001

4. Baking quality – Protein structure
Protein composition - Genotype
Veraverbeke and Delcour 2002

5. Protein polymers
Influences of cultivar, year and N rate
0,7 120
Relative protein amount
0,6 100
0,5
80 LUPP
0,4 Serie1
60
0,3 Prot
40 Glut
0,2
0,1 20
0 0
1991 1996 1995 1994
1,6 50
Year 45
1,4
40
1,2
35
1 LUPP
30
TUPP
0,8 25
prot*3
0,6 20
glut
15
0,4
10
0,2 5
0 0
70+70 140
Johansson et al. 2001, 2004

6. Weather influences quality
Johansson et al. 2002

7. Polymeric protein and quality
Why different depending on cultivar and weather?
Protein polymer size, shape and amount of
disulfide bonds
- What is the reason?
•Amount protein/protein types?
•Amount and type of bindings?
•Involvements of enzymes?
•Grain development period – which role
does it play?

8. Built-up of polymeric proteins
80
75
% LUPP
70
N låg
N hög
65 0 10 20 30 40 50 60
Dagar efter blomning
 Time to anthesis  Nitrogen availability
 Time of grain development  Temperature
Johansson et al. JSFA. 2005

9. Malik et al. JSFA. 2011

10. Malik et al. JSFA. 2011

11. Malik et al. J Cereal Sci. 2013

12. Malik et al. J Cereal Sci. 2013

13. Polymeric protein in the wheat grain
Why different depending on cultivar and weather?
-What is the reason?
•Genotype – protein composition – number of SS-bonds
•Genotype-environment – length of time to anthesis – protein
concentration – gli/glu relationships
•Genotype-environment – length of/N availability at grain
filling period – protein concentration – gli/glu relationships
•Environment – temperature – enzymes - PDI

14. Protein polymers in dough
Kuktaite et al. J Cereal Sci. 2004

15. Reasons for polymer formation in dough
Rombouts et al. J Cereal Sci. 2010

16. Hussain et al. J Cereal Sci. 2013

17. Plastic materials and foams

18. Additives and tensile strength
Table. Influences of different additives on tensile strength in wheat gluten bio-
plastics films.
________________________________________________________
Additive Relative tensile strength parameters
__________________________________________
Fracture stress Fracture strain Young’s modulus
(MPa) (%) (MPa)
________________________________________________________
Pure gluten 100 100 100
Salicylic acid 100 81 100
NaOH 185 151 340
Hemp fibre 108 14 473
Diamine 130 82 136
Nano 164 73 134
Ammonium 300 28
________________________________________________________

19. Much stronger Better structure More even
Best trial protein composition
7.5AH
6
10AH
5AH
4
Stress in MPa
2
WGG
0
0 20 40 60 80 100 120
Strai n i n %
Mängd extraherade proteiner i olika prover vid 0
dagar
100000000
80000000
60000000
40000000
20000000
Proteins almost 0
unextractable tote totu tot2u
Ullsten et al. Polym Renew Resourc. 2010

20. Kuktaite et al. Biomacromol. 2011

21. Kuktaite et al. Biomacromol. 2011

22. Kuktaite et al. Biomacromol. 2011